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The purpose of this study was to investigate the tribological properties of bulk Fe₂B with pre-oxidation treatment.

Bulk Fe₂B was oxidized in an electric box furnace with a soaking time of 9 min under 750°C in air. Then, the tribological experiments were carried out on an UMT-Tribolab tester.

The oxide layer was composed of Fe, Fe₂O₃, Fe₃O₄, B₂O₃ and H₃BO₃. The oxidative direction of bulk Fe₂B was perpendicular to the sample surface. But, the oxidative direction of Fe₂B crystals was irregular. At 0.1 m/s, the friction coefficient was the lowest. The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment at 0.1 m/s were remarkable. Nevertheless, the effect of pre-oxidation treatment was futile at 0.2 m/s. Wear mechanisms of oxidized Fe₂B mainly were adhesive and abrasive wear.

The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment were remarkable.

This paper aims to demonstrate the effect of varying chromium content on the wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron, while estimating their contribution rate in abrasive wear.

To study interaction of cementite-pearlite of white cast irons with different chromium content in three-body abrasive wear, three kinds of chromium white cast iron, bulk single-phase cementite, pure pearlite samples and the white cast iron (WCI), were prepared using the melting and casting technique. The so-called pure pearlite samples have the same chemical composition, microstructure and properties as the pearlite matrix in white cast iron.

Results indicated that the interaction has a negative value. Its absolute value decreased with increasing chromium addition. Meanwhile, a high load resulted in an increased interaction value. The contribution rate of cementite to interaction, which was higher than that of pearlite, increased with increasing chromium addition. This indicated cementite was a main phase. Besides, the reductive size of abrasive has a significant effect on the contribution rate at the high load. These prominent cementite occurred fracture, when small size abrasive indented the matrix. These result in the absence of a protective effect of cementite during wear process. Eventually, the contribution rate of cementite decreased significantly.

This paper demonstrates the effect of varying chromium content on wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron while estimating their contribution rate in abrasive wear.

This paper seeks to answer two questions: (1) where do a country's entrepreneurship policies come from? (2) How do they evolve and shape entrepreneurial activities?

Drawing upon the comparative political economy literature and the institutional perspective, this paper proposes a theoretical model of the origin and evolution of entrepreneurship policies. We use China as a case study to apply the theoretical model and demonstrate the evolution of entrepreneurship policies in three stages during the period 1978 to 2012.

The case analysis of China provides evidence and support for our theoretical model and unpacks the process by which entrepreneurship policies originate and evolve as the result of the interplay among constantly changing policymaking, production, and knowledge regimes.

Because of the research context, findings may lack generalisability. Additional studies on policymaking and production regimes of different kinds and their respective roles in shaping entrepreneurship policies are encouraged to further advance this line of research.

This paper offers important implications concerning entrepreneurship policy and activities for policymakers, practitioners and other stakeholders in emerging economies.

Our study fills a gap in the entrepreneurship literature by expanding scholarly understanding of the origin and evolution of entrepreneurship policies.

The purpose of this paper is to explore the variation law between the clay microstructure and macro external force by using soil scanning electron microscope (SEM) images.

First, SEM images of clay were pre-processed by MATLAB, and quantitative statistical parameters such as directional probability entropy, fractal dimension and shape factor are extracted. Second, the distribution force model was proposed, considering that the microscopic parameters of soil particles were independent of each other, and the distribution coefficient was determined according to the analytic hierarchy process (AHP). Then, the fitted formula of quantitative statistical parameters based on the distribution force model was obtained by taking the macroscopic distribution force as independent variable and the microscopic parameters of soil particles as dependent variable. Finally, the correctness of corresponding fitting formula was verified.

The results showed that the change of external consolidation pressure has great influence on the directional probability entropy and fractal dimension, while the shape factor reflecting the regular degree of soil particle shape is less sensitive to the consolidation pressure. The fitting formula has high accuracy, and mostly the R value can reach more than 0.9. All the data have passed the test, which proves that the distribution force model proposed in this paper is rational.

The model can be used to connect the macroscopic stress of soil with the micro-structure deformation of soil particles through mathematical formula, which can provide reference for engineering practice.

Based on government data from 1993 to 2008, this chapter aims to compute and analyze the trends of inequity in interprovincial and regional per-student spending in China's compulsory education, and to ascertain the potential impact of changes in education financing policies. Appropriate inequity measures (Gini and Theil index and Gini decomposition, among others) are employed to provide a systematic picture of the trends. Main findings include: (1) all inequity measures show large and overall increased disparities among provinces and among regions, between 1993 and 2008. (2) However, a slight drop of spending inequity is observed at the primary education level around 2002 and a larger reduction in 2005 and on. There are more turning points in the trend of lower-secondary per-student spending among provinces. These patterns are consistent across different inequity measures and spending indicators (per-student total spending, per-student recurrent spending, and per-student nonpersonnel spending). (3) The trend toward more balanced resource allocation around 2002 and 2005 could be the impact from the Reform of Tax and Administrative Charges and the New Mechanism for Financing Rural Compulsory Education. An increased share of budgetary expenditure in determining total spending suggests that equalizing financing policies have the potential to induce a significant reduction in spending inequity. These findings may help policy makers to better understand and alter the extent of spending inequity in compulsory education. This is an original empirical study that systematically derives the spending inequity trends over a long period in China's compulsory education.